Genetic Regulation Of Hip Geometry, Structure And Fracture
Funder
National Health and Medical Research Council
Funding Amount
$403,625.00
Summary
Osteoporotic hip fracture is common in the elderly and a major cause of hospitalization. Hip fracture may lead to surgery, chronic reduced mobility, loss of function, institutionalization or death. The term osteoporosis covers a heterogeneous syndrome including juvenile, secondary (e.g. corticosteroid induced) and postmenopausal osteoporosis. This later broad grouping shows evidence of a strong familial association. Previous work has shown that a family history of fracture increases the risk of ....Osteoporotic hip fracture is common in the elderly and a major cause of hospitalization. Hip fracture may lead to surgery, chronic reduced mobility, loss of function, institutionalization or death. The term osteoporosis covers a heterogeneous syndrome including juvenile, secondary (e.g. corticosteroid induced) and postmenopausal osteoporosis. This later broad grouping shows evidence of a strong familial association. Previous work has shown that a family history of fracture increases the risk of fracture by more than four fold. Furthermore, studies in twins have persistently shown that phenotypes such as bone mineral density (BMD), broadband ultrasound attenuation of bone and hip structural indices are strongly inherited. This confirms a genetic basis for the disease in some individuals. Community health in general has improved substantially in Australia in the past four decades and this has resulted in increased longevity. In contrast, the incidence of hip fracture and the resulting drain on public health funding continues to increase rapidly. Presently the cost of osteoporosis in Australia is $7.5 billion per annum. Hip fracture accounts for the majority of these costs. Instituting effective prevention strategies is essential. This project aims to contribute to one of Australia's National Research Pritoities by improving understanding about the way in which inherited aspects of hip geometry and structure contribute to the hip fracture susceptibility. We have successfully completed genome screen projects studying genetic linkage in the families to localize genes regulating BMD in the past. However, BMD is only one of a number of relevant phenotypes. In relation to hip fracture, geometry and structure are thought to be particularly important. In this project we will make use of existing resources to advance studies of both genetic linkage and association to examine fundamental issues related to hip facture.Read moreRead less
Radiostereometric Analysis Of The Effect Of A Large Articulation On Prosthetic Wear And Migration After Hip Replacement
Funder
National Health and Medical Research Council
Funding Amount
$192,186.00
Summary
At total hip replacement, there has been a recent trend to use prostheses with a larger ball and liner in the socket. This may decrease the risk of post-operative dislocation, but may also increase the amount of wear, leading to bone loss and loosening of prostheses, which may then require replacement. This project will use a special type of x-ray to determine whether wear and movement of these new prostheses is clinically acceptable, so that they can be used with confidence in patients.
Regulation Of Key Pathways Causing Peri-implant Bone Loss.
Funder
National Health and Medical Research Council
Funding Amount
$403,639.00
Summary
The failure of bone prostheses is becoming a major health problem in our aging population. Despite the impressive success of joint replacement surgery, a significant number of arthroplasties fail. It is now apparent that most implants fail due to bone loss around them which leads to loosening. This project aims to obtain a better understanding of the causes of implant failure and find ways to extend the life of these implants .
Determination Of Irradiation Dose Efficacy For Use In Impaction Grafting At Revision Joint Replacement
Funder
National Health and Medical Research Council
Funding Amount
$411,517.00
Summary
Primary hip replacement is a successful intervention for hip disease, but 10-15% of hip prostheses fail and require revision surgery within 10-15 years. At the time of revision, significant bone loss around the failed prosthesis is not uncommon. A bone reconstruction procedure, called impaction grafting, where donor bone is minced and placed in the areas of deficient bone before implanting the new prosthesis, has shown to give good results at more than ten years in some centres. A high incidence ....Primary hip replacement is a successful intervention for hip disease, but 10-15% of hip prostheses fail and require revision surgery within 10-15 years. At the time of revision, significant bone loss around the failed prosthesis is not uncommon. A bone reconstruction procedure, called impaction grafting, where donor bone is minced and placed in the areas of deficient bone before implanting the new prosthesis, has shown to give good results at more than ten years in some centres. A high incidence of early complications of this procedure have included loss of fixation within the bone. Fracture of the bone around prostheses has also reported in some centres. These events require more surgery, putting the patient at higher risk greater complications and longer rehabilitations. Recent improvements in surgical technique and donor bone preparation have improved results. A current debate questions whether the dose of irradiation can be reduced from 25 kGy, while maintaining sterility of allografts. The risk of bacterial contamination in allografts is low, and irradiation reduces the mechanical strength of the graft, contributing to complications when irradiated bone is used. The benefits of decontaminating the bone may be outweighed by the higher risk for failure due to poor bone quality and resulting prosthesis instability. We will use ISO standards to test the validity of radiation dose for sterilising bone ex vivo. In the absence of controlled human studies, our aim is also to compare the results of impaction grafting with non-irradiated bone versus bone irradiated at current doses used by Australian bone banks, and lower doses indicated by ex vivo testing. We will use a large animal model of revision hip replacement, with precise measures of prosthesis stability. The results of this study will guide clinical decisions regarding the efficacy of current bone graft preparation procedures and the use of irradiated bone in human hip replacement surgery.Read moreRead less